# 2 - Snake ### Video {% embed url="" %} ### Code ```python from machine import Pin, PWM import time from random import randint import _thread class LED_Matrix(): def __init__(self): # Create a list of pin numbers self.row_pins = [6,4,7,5,3,8,2,9] self.row_pins.reverse() self.col_pins = [10,11,12,13,18,19,20,21] self.col_pins.reverse() # Create empty lists to contain the Pin objects self.rows = [] self.cols = [] # Use the list of pin numbers to create # Pin objects and add them to the lists # created above. for i in self.row_pins: self.rows.append(Pin(i, Pin.OUT)) for i in self.col_pins: self.cols.append(Pin(i, Pin.OUT)) # Create empty 8x8 array self.matrix = [ [0,0,0,0,0,0,0,0], [0,0,0,0,0,0,0,0], [0,0,0,0,0,0,0,0], [0,0,0,0,0,0,0,0], [0,0,0,0,0,0,0,0], [0,0,0,0,0,0,0,0], [0,0,0,0,0,0,0,0], [0,0,0,0,0,0,0,0] ] # Create a counter for current column self.cur_col = 0 def clear(self): self.matrix = [ [0,0,0,0,0,0,0,0], [0,0,0,0,0,0,0,0], [0,0,0,0,0,0,0,0], [0,0,0,0,0,0,0,0], [0,0,0,0,0,0,0,0], [0,0,0,0,0,0,0,0], [0,0,0,0,0,0,0,0], [0,0,0,0,0,0,0,0] ] def next_row(self): # Deactivate current row self.cols[self.cur_col].value(0) # Increment current row self.cur_col = (self.cur_col + 1) % 8 # Load next row's columns for i in range(8): self.rows[i].value(self.matrix[self.cur_col][i]) # Activate next row self.cols[self.cur_col].value(1) def draw(self, tup_list): for row , col in tup_list: self.matrix[col][row] = 1 class Snake(): def __init__(self): self.pos = [(4,4)] # A list of tuples that contains coordinates for each segment self.len = 2 # Current length of the snake self.dx = 1 # Change in X position per frame self.dy = 0 # Change in Y position per frame self.notes = [262,294,330,349,392,440,495,523,587,659,698,784,880,988,1047,1175,1319,1397,1568,1760,1976,2093] self.cur_note = 0 self.spkr = PWM(Pin(22)) # Create PWM object for speaker self.sprk_vol = 2**10 self.spawn_apple() # Call a method to spawn an apple def spawn_apple(self): self.apple = [(randint(0,7),randint(0,7))] # Spawn Apple at Random Location # Retry if it landed on the snake for tup in self.pos: if tup == self.apple[0]: self.spawn_apple() def ate_apple(self): print(f'Ate an apple!') self.len += 1 self.cur_note += 1 self.spkr.freq(self.notes[self.cur_note]) # Set frequency in Hz self.spkr.duty_u16(self.sprk_vol) time.sleep_ms(100) self.spkr.duty_u16(0) # Set duty to 0 self.spawn_apple() def reset(self): print('Reset') for self.i in range (self.cur_note, -1, -1): print(f'Note{self.i}') self.spkr.freq(self.notes[self.i]) self.spkr.duty_u16(self.sprk_vol) time.sleep_ms(200) self.spkr.duty_u16(0) # Set duty to 0 time.sleep_ms(50) self.len = 2 self.cur_note = 0 self.spawn_apple() def up(self): print('up') # Prevent Snake from flipping back on itself if self.dy == -1: return # Otherwise set direction to up else: self.dx = 0 self.dy = 1 def down(self): print('down') # Prevent Snake from flipping back on itself if self.dy == 1: return # Otherwise set direction to down else: self.dx = 0 self.dy = -1 def left(self): print('left') # Prevent Snake from flipping back on itself if self.dx == 1: return # Otherwise set direction to left else: self.dx = -1 self.dy = 0 def right(self): print('right') # Prevent Snake from flipping back on itself if self.dx == -1: return # Otherwise set direction to right else: self.dx = 1 self.dy = 0 def update(self): # Get current position of snake head self.x, self.y = self.pos[0] # Move the head to the new position self.x += self.dx self.y += self.dy # Ensure the new position stays within bounds self.x = self.x % 8 self.y = self.y % 8 # Add new position to front of position list self.pos.insert(0,(self.x,self.y)) # Detect Apple Collision if self.pos[0] == self.apple[0]: self.ate_apple() # Detect Self Collision for self.i in range(1,len(self.pos)): if self.pos[0] == self.pos[self.i]: self.reset() # Ensure snake only grows when eating apples while len(self.pos) > self.len: self.pos.pop() def update_display(): while True: global d d.next_row() time.sleep_ms(2) def game_loop(): # Connect to globals global d global s # Create Button Objects up = Pin(14, Pin.IN, Pin.PULL_UP) down = Pin(17, Pin.IN, Pin.PULL_UP) left = Pin(16, Pin.IN, Pin.PULL_UP) right = Pin(1, Pin.IN, Pin.PULL_UP) # Main Loop for game, runs at 10 Hz while True: # Get button inputs if not up.value(): s.up() if not down.value(): s.down() if not left.value(): s.left() if not right.value(): s.right() # Update Snake s.update() # Clear Display d.clear() # Draw Snake on Display print(s.pos) try: d.draw(s.pos) except: print('Could not draw snake, initiating reset.') s.reset() # Draw Apple on Display print(s.apple) try: d.draw(s.apple) except: print('Could not draw apple, initiating reset.') s.reset() # Do nothing for 100ms, (10Hz Frame-Rate) time.sleep_ms(100) # Create LED Matrix object d = LED_Matrix() # Create Snake Object s = Snake() # Use second core to constantly run the display _thread.start_new_thread(update_display,()) # Use main core to run game loop at 10Hz game_loop() ``` --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. 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